Shooting In Blacklight? at DVinfo.net

Kray Mitchell · October 29th, 2003, 12:21 PM

I am wondering if anybody here has had success shooting in Blacklights with the GL2, I run into the Issue of the light turning out Green instead of Purple.

I am wondering if there are any settings that I can change to make this work, or if I would have to get some sort of filter for it (Or is it even Possible on DV!)

Anyway, I hope somebody here knows, I can't seem to find any information about it and I have a client that would like to do this for a music video!

Curt Kay · November 1st, 2003, 04:01 PM

cameras in general have a problem with the color purple. I read on some other post about this.

Try a search on "purple"

-kay

Kray Mitchell · November 3rd, 2003, 10:16 AM

Curt,
Thanks for the tip, I will check it out!

Jeff Price · November 3rd, 2003, 12:04 PM

Did you manually white-balance the camera first? This is defintiely a case where I would not tust the auto white-balance. Try setting the white-balance under the conditions you will be shooting and see if it helps.

Kray Mitchell · November 8th, 2003, 11:17 AM

Jeff,
I never trust the auto-white's, or the auto anything for that matter!
I still cannot find anything about this anywhere I seem to look.

I can't believe that with this many people on this board that NOBODY has shot in blacklight before!!! (Ive seen movies where it was done, sombody has to know!)

Don Palomaki · November 9th, 2003, 07:14 AM

Back lighting is a major probolem for any imaging system if you want to obtain detail in the back-lit subject rather than just a silhouette effect.

Try increasing the exposure manually or using the exposure adjustment features of the camcorder. Avoid having a very hot spot/light source in the visible background of the image. You could try some added fill lighting to improve shadow detail.

Kray Mitchell · November 10th, 2003, 12:14 PM

no, no, BLACKlight, not backlight :o)

thanX though ;o)

Jeff Price · November 11th, 2003, 10:07 AM

Kray,

Many CCDs are sensitive to wavelengths beyond those the human eye can see. Coatings are supposed to sut down on some of these but not necessarily all. For example, many digital cameras have IR filters specifically to remove the IR wavelengths - otherwise we would need what are called Hot filters.

It is possible that the effect you are seeing is from the additional near UV wavelengths. If that is the case then the only way to solve the issue would be with a proper UV filter. There was a thread on here recently that pointed to a web site reviewing many of the popular UV filters. Turned out that many of them didn't block much of anything (I think the Hoya was an exception).

It might be worth trying some different UV filters to see if it skews the colors back toward purple.

Kray Mitchell · November 12th, 2003, 10:55 AM

Jeff,
Excellent suggestion, I will see if I can find those reviews and gt a filter based on that and see if it works!

October 29th, 2003, 12:21 PM	#1
Kray Mitchell New Boot Join Date: Oct 2003 Location: Calgary, AB Posts: 18	Shooting In Blacklight? I am wondering if anybody here has had success shooting in Blacklights with the GL2, I run into the Issue of the light turning out Green instead of Purple. I am wondering if there are any settings that I can change to make this work, or if I would have to get some sort of filter for it (Or is it even Possible on DV!) Anyway, I hope somebody here knows, I can't seem to find any information about it and I have a client that would like to do this for a music video! __________________ iThink, therefore iMac ---------------------------------------------------- www.emotiondv.com DV Discussion for the rest of us

November 1st, 2003, 04:01 PM	#2
Curt Kay Regular Crew Join Date: Sep 2003 Location: San Jose, Ca Posts: 50	cameras in general have a problem with the color purple. I read on some other post about this. Try a search on "purple" -kay __________________ Fight the power. http://www.curtkay.com I WILL not be held down.

November 3rd, 2003, 10:16 AM	#3
Kray Mitchell New Boot Join Date: Oct 2003 Location: Calgary, AB Posts: 18	Curt, Thanks for the tip, I will check it out! __________________ iThink, therefore iMac ---------------------------------------------------- www.emotiondv.com DV Discussion for the rest of us

November 3rd, 2003, 12:04 PM	#4
Jeff Price Major Player Join Date: Apr 2003 Location: Chico, California Posts: 357	Did you manually white-balance the camera first? This is defintiely a case where I would not tust the auto white-balance. Try setting the white-balance under the conditions you will be shooting and see if it helps. __________________ Jeff Price Flickerflix Nature Videos flickerflix@yahoo.com

November 8th, 2003, 11:17 AM	#5
Kray Mitchell New Boot Join Date: Oct 2003 Location: Calgary, AB Posts: 18	Jeff, I never trust the auto-white's, or the auto anything for that matter! I still cannot find anything about this anywhere I seem to look. I can't believe that with this many people on this board that NOBODY has shot in blacklight before!!! (Ive seen movies where it was done, sombody has to know!) __________________ iThink, therefore iMac ---------------------------------------------------- www.emotiondv.com DV Discussion for the rest of us

November 9th, 2003, 07:14 AM	#6
Don Palomaki Wrangler Join Date: Sep 2001 Location: Northern VA Posts: 4,487	Back lighting is a major probolem for any imaging system if you want to obtain detail in the back-lit subject rather than just a silhouette effect. Try increasing the exposure manually or using the exposure adjustment features of the camcorder. Avoid having a very hot spot/light source in the visible background of the image. You could try some added fill lighting to improve shadow detail. __________________ dpalomaki@dspalomaki.com

November 10th, 2003, 12:14 PM	#7
Kray Mitchell New Boot Join Date: Oct 2003 Location: Calgary, AB Posts: 18	no, no, BLACKlight, not backlight :o) thanX though ;o) __________________ iThink, therefore iMac ---------------------------------------------------- www.emotiondv.com DV Discussion for the rest of us

November 11th, 2003, 10:07 AM	#8
Jeff Price Major Player Join Date: Apr 2003 Location: Chico, California Posts: 357	Kray, Many CCDs are sensitive to wavelengths beyond those the human eye can see. Coatings are supposed to sut down on some of these but not necessarily all. For example, many digital cameras have IR filters specifically to remove the IR wavelengths - otherwise we would need what are called Hot filters. It is possible that the effect you are seeing is from the additional near UV wavelengths. If that is the case then the only way to solve the issue would be with a proper UV filter. There was a thread on here recently that pointed to a web site reviewing many of the popular UV filters. Turned out that many of them didn't block much of anything (I think the Hoya was an exception). It might be worth trying some different UV filters to see if it skews the colors back toward purple. __________________ Jeff Price Flickerflix Nature Videos flickerflix@yahoo.com

November 12th, 2003, 10:55 AM	#9
Kray Mitchell New Boot Join Date: Oct 2003 Location: Calgary, AB Posts: 18	Jeff, Excellent suggestion, I will see if I can find those reviews and gt a filter based on that and see if it works! __________________ iThink, therefore iMac ---------------------------------------------------- www.emotiondv.com DV Discussion for the rest of us